[PATCH v3 05/10] fs: simplify ->listxattr() implementation
Christian Brauner
brauner at kernel.org
Thu Feb 2 00:14:56 AEDT 2023
The ext{2,4}, erofs, f2fs, and jffs2 filesystems use the same logic to
check whether a given xattr can be listed. Simplify them and avoid
open-coding the same check by calling the helper we introduced earlier.
Reviewed-by: Christoph Hellwig <hch at lst.de>
Cc: linux-f2fs-devel at lists.sourceforge.net
Cc: linux-erofs at lists.ozlabs.org
Cc: linux-ext4 at vger.kernel.org
Cc: linux-mtd at lists.infradead.org
Signed-off-by: Christian Brauner (Microsoft) <brauner at kernel.org>
---
Changes in v3:
- Patch unchanged.
Changes in v2:
- Christoph Hellwig <hch at lst.de>:
- Rework this patch completey by keeping the legacy generic POSIX ACL
handlers around so that array-based handler indexing still works.
This means way less churn for filesystems.
---
fs/erofs/xattr.c | 8 ++------
fs/erofs/xattr.h | 14 +++++++++++---
fs/ext2/xattr.c | 17 ++++++++++-------
fs/ext4/xattr.c | 17 ++++++++++-------
fs/f2fs/xattr.c | 16 ++++++++++------
fs/jffs2/xattr.c | 21 ++++++++++++---------
6 files changed, 55 insertions(+), 38 deletions(-)
diff --git a/fs/erofs/xattr.c b/fs/erofs/xattr.c
index 2c98a15a92ed..4b73be57c9f4 100644
--- a/fs/erofs/xattr.c
+++ b/fs/erofs/xattr.c
@@ -492,13 +492,9 @@ static int xattr_entrylist(struct xattr_iter *_it,
unsigned int prefix_len;
const char *prefix;
- const struct xattr_handler *h =
- erofs_xattr_handler(entry->e_name_index);
-
- if (!h || (h->list && !h->list(it->dentry)))
+ prefix = erofs_xattr_prefix(entry->e_name_index, it->dentry);
+ if (!prefix)
return 1;
-
- prefix = xattr_prefix(h);
prefix_len = strlen(prefix);
if (!it->buffer) {
diff --git a/fs/erofs/xattr.h b/fs/erofs/xattr.h
index 0a43c9ee9f8f..08658e414c33 100644
--- a/fs/erofs/xattr.h
+++ b/fs/erofs/xattr.h
@@ -41,8 +41,11 @@ extern const struct xattr_handler erofs_xattr_user_handler;
extern const struct xattr_handler erofs_xattr_trusted_handler;
extern const struct xattr_handler erofs_xattr_security_handler;
-static inline const struct xattr_handler *erofs_xattr_handler(unsigned int idx)
+static inline const char *erofs_xattr_prefix(unsigned int idx,
+ struct dentry *dentry)
{
+ const struct xattr_handler *handler = NULL;
+
static const struct xattr_handler *xattr_handler_map[] = {
[EROFS_XATTR_INDEX_USER] = &erofs_xattr_user_handler,
#ifdef CONFIG_EROFS_FS_POSIX_ACL
@@ -57,8 +60,13 @@ static inline const struct xattr_handler *erofs_xattr_handler(unsigned int idx)
#endif
};
- return idx && idx < ARRAY_SIZE(xattr_handler_map) ?
- xattr_handler_map[idx] : NULL;
+ if (idx && idx < ARRAY_SIZE(xattr_handler_map))
+ handler = xattr_handler_map[idx];
+
+ if (!xattr_handler_can_list(handler, dentry))
+ return NULL;
+
+ return xattr_prefix(handler);
}
extern const struct xattr_handler *erofs_xattr_handlers[];
diff --git a/fs/ext2/xattr.c b/fs/ext2/xattr.c
index 262951ffe8d0..958976f809f5 100644
--- a/fs/ext2/xattr.c
+++ b/fs/ext2/xattr.c
@@ -121,14 +121,18 @@ const struct xattr_handler *ext2_xattr_handlers[] = {
#define EA_BLOCK_CACHE(inode) (EXT2_SB(inode->i_sb)->s_ea_block_cache)
-static inline const struct xattr_handler *
-ext2_xattr_handler(int name_index)
+static inline const char *ext2_xattr_prefix(int name_index,
+ struct dentry *dentry)
{
const struct xattr_handler *handler = NULL;
if (name_index > 0 && name_index < ARRAY_SIZE(ext2_xattr_handler_map))
handler = ext2_xattr_handler_map[name_index];
- return handler;
+
+ if (!xattr_handler_can_list(handler, dentry))
+ return NULL;
+
+ return xattr_prefix(handler);
}
static bool
@@ -329,11 +333,10 @@ ext2_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size)
/* list the attribute names */
for (entry = FIRST_ENTRY(bh); !IS_LAST_ENTRY(entry);
entry = EXT2_XATTR_NEXT(entry)) {
- const struct xattr_handler *handler =
- ext2_xattr_handler(entry->e_name_index);
+ const char *prefix;
- if (handler && (!handler->list || handler->list(dentry))) {
- const char *prefix = handler->prefix ?: handler->name;
+ prefix = ext2_xattr_prefix(entry->e_name_index, dentry);
+ if (prefix) {
size_t prefix_len = strlen(prefix);
size_t size = prefix_len + entry->e_name_len + 1;
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index ba7f2557adb8..3fbeeb00fd78 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -169,14 +169,18 @@ static void ext4_xattr_block_csum_set(struct inode *inode,
bh->b_blocknr, BHDR(bh));
}
-static inline const struct xattr_handler *
-ext4_xattr_handler(int name_index)
+static inline const char *ext4_xattr_prefix(int name_index,
+ struct dentry *dentry)
{
const struct xattr_handler *handler = NULL;
if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map))
handler = ext4_xattr_handler_map[name_index];
- return handler;
+
+ if (!xattr_handler_can_list(handler, dentry))
+ return NULL;
+
+ return xattr_prefix(handler);
}
static int
@@ -691,11 +695,10 @@ ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry,
size_t rest = buffer_size;
for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
- const struct xattr_handler *handler =
- ext4_xattr_handler(entry->e_name_index);
+ const char *prefix;
- if (handler && (!handler->list || handler->list(dentry))) {
- const char *prefix = handler->prefix ?: handler->name;
+ prefix = ext4_xattr_prefix(entry->e_name_index, dentry);
+ if (prefix) {
size_t prefix_len = strlen(prefix);
size_t size = prefix_len + entry->e_name_len + 1;
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
index ccb564e328af..9de984645253 100644
--- a/fs/f2fs/xattr.c
+++ b/fs/f2fs/xattr.c
@@ -212,13 +212,18 @@ const struct xattr_handler *f2fs_xattr_handlers[] = {
NULL,
};
-static inline const struct xattr_handler *f2fs_xattr_handler(int index)
+static inline const char *f2fs_xattr_prefix(int index,
+ struct dentry *dentry)
{
const struct xattr_handler *handler = NULL;
if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map))
handler = f2fs_xattr_handler_map[index];
- return handler;
+
+ if (!xattr_handler_can_list(handler, dentry))
+ return NULL;
+
+ return xattr_prefix(handler);
}
static struct f2fs_xattr_entry *__find_xattr(void *base_addr,
@@ -569,12 +574,12 @@ ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
last_base_addr = (void *)base_addr + XATTR_SIZE(inode);
list_for_each_xattr(entry, base_addr) {
- const struct xattr_handler *handler =
- f2fs_xattr_handler(entry->e_name_index);
const char *prefix;
size_t prefix_len;
size_t size;
+ prefix = f2fs_xattr_prefix(entry->e_name_index, dentry);
+
if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
(void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) {
f2fs_err(F2FS_I_SB(inode), "inode (%lu) has corrupted xattr",
@@ -586,10 +591,9 @@ ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
goto cleanup;
}
- if (!handler || (handler->list && !handler->list(dentry)))
+ if (!prefix)
continue;
- prefix = xattr_prefix(handler);
prefix_len = strlen(prefix);
size = prefix_len + entry->e_name_len + 1;
if (buffer) {
diff --git a/fs/jffs2/xattr.c b/fs/jffs2/xattr.c
index 0eaec4a0f3b1..1189a70d2007 100644
--- a/fs/jffs2/xattr.c
+++ b/fs/jffs2/xattr.c
@@ -924,8 +924,9 @@ const struct xattr_handler *jffs2_xattr_handlers[] = {
NULL
};
-static const struct xattr_handler *xprefix_to_handler(int xprefix) {
- const struct xattr_handler *ret;
+static const char *jffs2_xattr_prefix(int xprefix, struct dentry *dentry)
+{
+ const struct xattr_handler *ret = NULL;
switch (xprefix) {
case JFFS2_XPREFIX_USER:
@@ -948,10 +949,13 @@ static const struct xattr_handler *xprefix_to_handler(int xprefix) {
ret = &jffs2_trusted_xattr_handler;
break;
default:
- ret = NULL;
- break;
+ return NULL;
}
- return ret;
+
+ if (!xattr_handler_can_list(ret, dentry))
+ return NULL;
+
+ return xattr_prefix(ret);
}
ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
@@ -962,7 +966,6 @@ ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
struct jffs2_inode_cache *ic = f->inocache;
struct jffs2_xattr_ref *ref, **pref;
struct jffs2_xattr_datum *xd;
- const struct xattr_handler *xhandle;
const char *prefix;
ssize_t prefix_len, len, rc;
int retry = 0;
@@ -994,10 +997,10 @@ ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
goto out;
}
}
- xhandle = xprefix_to_handler(xd->xprefix);
- if (!xhandle || (xhandle->list && !xhandle->list(dentry)))
+
+ prefix = jffs2_xattr_prefix(xd->xprefix, dentry);
+ if (!prefix)
continue;
- prefix = xhandle->prefix ?: xhandle->name;
prefix_len = strlen(prefix);
rc = prefix_len + xd->name_len + 1;
--
2.34.1
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